Police in Los Angeles are testing a knife recovered on a property once owned by O.J. Simpson, who was acquitted in the murder of his former wife and her friend, the Los Angeles Police Department said on Friday.

The department is investigating the buck knife with a retractable blade, which was apparently turned over to a police officer a number of years ago by a construction worker at the property, the Los Angeles Times newspaper reported, citing an unnamed law enforcement source.

Los Angeles Police spokeswoman Norma Eisenman said the agency’s Robbery Homicide Division was investigating. She declined to provide further details.

Simpson, a retired pro football Hall of Fame running back for the National Football League’s Buffalo Bills, was acquitted in 1995 of murdering his former wife and her friend, Ronald Goldman, in Los Angeles. He later lost a wrongful death lawsuit brought by the victims’ families.

Simpson is now in prison on a 2008 armed robbery conviction related to the robbery of two sports memorabilia dealers at a Las Vegas hotel.